1. Field of the Invention
The present invention relates to a surface acoustic wave element and a method of manufacturing the same, and more specifically, to a surface acoustic wave element and a method of manufacturing the same, the element including a piezoelectric substrate, a plurality of IDT electrodes formed on the piezoelectric substrate; a plurality of resonator electrodes formed on the piezoelectric substrate; a wiring metal layer formed as a wiring area to electrically connect the plurality of IDT electrodes and the plurality of resonator electrodes; and an insulation layer formed on the piezoelectric substrate, the plurality of IDT electrodes, the plurality of resonator electrodes and the wiring metal layer.
2. Background of the Related Art
A surface acoustic wave (SAW) filter generates a surface acoustic wave on the surface of a substrate when an electrical signal is input from any one direction, and such a mechanical wavelength is converted into an electrical signal again, and only signals of the same frequency remain in this process. Accordingly, the surface acoustic wave filter functions as a filter passing only the frequencies of the same mechanical frequency that the filter has.
Recently, in response to a request for manufacturing a small and thin surface acoustic wave filter, a technique of manufacturing a surface acoustic wave filter using a wafer level package (WLP) method, which is a method of drilling a hole in a silicon wafer, inserting a light emitting diode chip therein and packaging the filter, is developed as a packaging technique combining a silicon semiconductor processing technique and a light emitting diode technique. Compared with an existing chip scale package (CSP) method of bonding a piezoelectric element and a separate substrate, the WLP method has an advantage of completing a product using only the piezoelectric element.
At this point, the surface acoustic wave filter is manufactured by forming a cavity on the piezoelectric element, and there is a problem in that if the adhesive force between the piezoelectric element, electrodes and a wiring metal layer is lowered in forming the cavity, the probability of generating a fault in a part is very high in an environment in which high humidity is maintained.